1. Field of the Invention
The present invention relates generally to apparatus designed for extracting electrical connectors, and more particularly to levered connector extractors of the type employing mechanical advantage principals.
2. Description of Prior Art
Multipin electrical connectors are secured into mating sockets by the clamping forces exerted by individual connecting sockets on mating connector pins, and often are further secured by locking screws located at the ends of the connector shell. Removal of a connector having a large number of pins is often difficult for the unaided human hand. Sometimes resort is had to pulling the connector off by its associated cable or pigtail, despite widespread knowledge that this is considered poor practice--especially when the cable's wires are not potted to the connector. Pulling the connector off by its cable causes damage by pulling loose, or breaking individual wires.
In those instances where rows of connectors are placed on a chassis, with connectors in close proximity to each other, removal becomes even more difficult because of spatial considerations. The placement of several closely-spaced rows of connectors on a chassis or breadboard results in a dearth of room for use of human fingers, and/or conventional tools. There is thus a need for a device having a small foot print which is capable of being pivotally inserted between the respective flanges of the connector to apply a mechanical advantage through a normal plane, and thereby cause the connectors to be pried apart. Presently, the removal of individual connectors is often accomplished by the insertion of two long screwdrivers, or other unconstrained levers, under the edge of the flange which usually encircles the connector shell, and attempting to pry both levers in coordination. In some cases, rotating a flat-blade screwdriver will pry the connector loose, but in many cases there is insufficient room for this maneuver, and neighboring connectors get used as fulcrums. As a result the chances of damaging the connectors is further enhanced.
The problem is compounded in those instances where the connectors are gold plated and are used in certain aerospace applications. There is a need to remove or extract connectors without damaging the surface of the connector flanges. Scratches on the surface of the flanges promote corrosion and pitting which can and does lead to failures over prolonged time periods.
That the above-stated problem has been recognized by others is evident in that attempts to provide tools to specifically solve some of the problems discussed above are shown in U.S. Pat. No. 3,117,370 issued to J. F. Kauppi et al in 1964; in U.S. Pat. No. 3,267,564 issued to M. A. Stuhler in 1966; in U.S. Pat. No. 4,372,635 issued to John E. Waldschmidt in 1983; in U.S. Pat. No. 4,424,625 issued to Daniel L. Callahan in 1985; and in U.S. Pat. No. 4,468,858 issued to Norman B. Gulberg et al in 1984. U.S. Pat. No. 3,177,567 issued to Ivor H. Gehrman in 1956 addresses a similar issue in that it discloses a device to mate electrical connectors. However, none of the devices shown in any the Patents listed above meet the collective needs which are met by the invention as disclosed herein.
For example, the Kauppi Patent discloses a rotating fulcrum which requires a large foot print and is susceptible to imparting scratches on the surface of the flanges surrounding the connector bodies.
The Stuhler Patent discloses a device that employs a lever principle in plier-like handles to impart an extraction force to a connector. This device is similarly unsuitable for use where spatial constraints are present.
The Waldschmidt Patent discloses a lever device which similarly is unsuitable for close applications and in addition appears to inherently possess the propensity for scratching the surface of the flange as it exerts a prying force between the flanges of each connector end.
The Callahan Patent discloses a device which utilizes the wedge principal to impart a prying force to separate electrical connectors. This device is also unsuitable for use where spatial considerations are paramount and in addition the device would inherently cause the connector pins to be misaligned by the imparting of a torquing moment rather than a normal force.
While the Gulberg Patent disclosure appears to recognize the need to apply a separating force in a plane normal to the connector body and to further avoid scratching the connector flanges, the device utilizes an entirely different principle to apply the separating force and is not adapted for tight spatial applications.
The Gehrman Patent discloses a mechanical advantage tool which, upon initial inspection, appears suitable for compressing electrical connectors to form a tight fit. However, the Gehrman device has handles which preclude its use in tightly packed installations, and it does not appear to be suitable for removing or separating connectors.
Other art of interest which does not address the problem and is not adaptable for solution of the problem can be found in U.S. Pat. No. 3,357,085 issued to M. Martin; in U.S. Pat. No. 3,540,106 issued to M. J. Goldman, and in U.S. Pat. No. 4,467,512 issued to Edward E. Modes.
There is therefore a still unsolved need for an apparatus or device that is adaptable for insertion between the flanges of multipin electrical connectors in close proximity to each other to impart a normal force adequate to cause separation of said connectors without damaging said connectors or the flanges surrounding them. The device should have a small footprint, and be suitable for use with unmounted and mounted connectors. Finally the device should not be too complicated to use or expensive to make.
It is therefore an objective of the invention described below to provide an apparatus for separating multipin electrical connectors.
A further objective of the invention is to provide a apparatus for separating electrical connectors which is pivotally adapted for insertion between flanges where a small footprint is required.
A still further object of the invention is to provide a connector extractor which applies a normal force to cause separation of the connector flanges and thereby preclude damage to connector pins by bending moments, or scratching of the flanges.
And it is a still further object of the invention below to provide an inexpensive and easy to use device for separating electrical connectors which are either mounted or unmounted.